This invention relates to a rotary valve type quick coupling for interconnecting two pressure medium conduits.
In particular, the invention concerns a quick coupling of the above type comprising a coupling unit including a casing and a spherical rotary valve element formed with a socket, and a tubular connector nipple adapted to be guidingly received in the valve element socket. An elongate aperture in the casing permits the connector nipple to be introduced into the valve element socket and to be rotated conjointly with said valve element between a connect/disconnect position and a connected position.
A quick coupling of the above described type is previously shown in DE-AS 1 265 515. When using a spherical valve element, as in the coupling illustrated in this publication, there is a problem in guiding the valve element such that the introduction and disconnection of the connector nipple may be carried out smoothly. A condition is that there is a proper alignment between the socket in the valve element and the aperture in the coupling unit casing.
In the prior art coupling referred to above, the alignment problem is solved by having a spring biassed sleeve enter the opening (See FIG. 1 in DE-AS 1 265 515). This sleeve also serves as a safety lock means to prevent unintentional disconnection of the coupling in the connected position (See FIG. 2).
As being apparent from the drawing figures, this prior art solution to the alignment problem is constructively complicated, expensive in manufacturing and results in a rather awkward handling.